ExpandableListView

>extends ListView

>This differs from the ListView by allowing two levels: groups which can individually be expanded to show its children. The items come from the ExpandableListAdapter associated with this view.

>Following is an demo application: Click Here to download source code

Main Activity

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.widget.ExpandableListView;

import android.widget.ExpandableListView.OnChildClickListener;

import android.widget.Toast;

public class MainActivity extends Activity {

ExpandableListAdapter expandableListAdapter;

ExpandableListView expandableListView;

List<String> parentListHeader;

HashMap<String, List<String>> childListData;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main_layout);

initializeDisplayElements();

prepareExpandableListData();

expandableListAdapter = new ExpandableListAdapter(this,

parentListHeader, childListData);

expandableListView.setAdapter(expandableListAdapter);

expandableListView.setOnChildClickListener(new OnChildClickListener() {

@Override

public boolean onChildClick(ExpandableListView parent, View v,

int groupPosition, int childPosition, long id) {

Toast.makeText(

getApplicationContext(),

parentListHeader.get(groupPosition)

+ " : "

+ childListData.get(

parentListHeader.get(groupPosition))

.get(childPosition), Toast.LENGTH_SHORT)

.show();

return false;

}

});

}

/**

* This method is used to prepare the expandable list data parent and

* corresponding child items.

*/

private void prepareExpandableListData() {

parentListHeader = new ArrayList<String>();

childListData = new HashMap<String, List<String>>();

// adding parent data

parentListHeader.add("Micromax");

parentListHeader.add("Moto");

parentListHeader.add("Samsung");

// adding child data

List<String> micromax = new ArrayList<String>();

micromax.add("micromax Canvas Nitro");

micromax.add("micromax Canvas Knight");

micromax.add("micromax gold");

List<String> moto = new ArrayList<String>();

moto.add("moto-G");

moto.add("moto-E");

moto.add("moto-G2");

List<String> samsung = new ArrayList<String>();

samsung.add("samsung grand");

samsung.add("samsung Note 2");

samsung.add("samsung Galaxy");

childListData.put(parentListHeader.get(0), micromax);

childListData.put(parentListHeader.get(1), moto);

childListData.put(parentListHeader.get(2), samsung);

}

/**

* This method is used to initialize display elements present on layout

*/

private void initializeDisplayElements() {

expandableListView = (ExpandableListView) findViewById(R.id.expandableListView1);

}

}

Android APL Levels And Versions

What is API Level?

---

API Level is an integer value that uniquely identifies the framework API revision offered by a version of the Android platform.

The Android platform provides a framework API that applications can use to interact with the underlying Android system. The framework API consists of:

• A core set of packages and classes
• A set of XML elements and attributes for declaring a manifest file
• A set of XML elements and attributes for declaring and accessing resources
• A set of Intents
• A set of permissions that applications can request, as well as permission enforcements included in the system

Platform Version	API Level	VERSION_CODE	Notes
Android 4.4	19	KITKAT	Platform Highlights
Android 4.3	18	JELLY_BEAN_MR2	Platform Highlights
Android 4.2, 4.2.2	17	JELLY_BEAN_MR1	Platform Highlights
Android 4.1, 4.1.1	16	JELLY_BEAN	Platform Highlights
Android 4.0.3, 4.0.4	15	ICE_CREAM_SANDWICH_MR1	Platform Highlights
Android 4.0, 4.0.1, 4.0.2	14	ICE_CREAM_SANDWICH
Android 3.2	13	HONEYCOMB_MR2
Android 3.1.x	12	HONEYCOMB_MR1	Platform Highlights
Android 3.0.x	11	HONEYCOMB	Platform Highlights
Android 2.3.4 Android 2.3.3	10	GINGERBREAD_MR1	Platform Highlights
Android 2.3.2 Android 2.3.1 Android 2.3	9	GINGERBREAD
Android 2.2.x	8	FROYO	Platform Highlights
Android 2.1.x	7	ECLAIR_MR1	Platform Highlights
Android 2.0.1	6	ECLAIR_0_1
Android 2.0	5	ECLAIR
Android 1.6	4	DONUT	Platform Highlights
Android 1.5	3	CUPCAKE	Platform Highlights
Android 1.1	2	BASE_1_1
Android 1.0	1	BASE

Speech To Text

speech to text conversion feature quite creatively. In today’s world of Siri, voice commands are of utmost importance. Android natively provides feature of Speech to Text so why not to use it in our app!

At the end of this post you can download the source code

Step 1: Create Basic Android Project

Go to New > Project > Android Project. Give the project name as SpeechToText

Step 2: Create an Layout

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical" >

    

    <TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_gravity="center"

        android:text="Speach To Text Example"

        android:textAppearance="?android:attr/textAppearanceLarge" />

    <Button

        android:id="@+id/speakButton"

        android:layout_width="150dp"

        android:layout_height="wrap_content"

        android:layout_gravity="center"

        android:layout_marginTop="30dp"

        android:text="Speak" />

    <TextView

        android:id="@+id/displayTextView"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_gravity="center"

        android:layout_marginTop="30dp"

        android:textAppearance="?android:attr/textAppearanceLarge" />

</LinearLayout>

Step 3: Android Java Code 

package com.example.activity;

import java.util.ArrayList;

import com.example.speechtotext.R;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.speech.RecognizerIntent;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

import android.widget.Toast;

public class SpeechActivity extends Activity {

TextView displayText;

@Override

protected void onCreate(Bundle savedInstanceState) {

// TODO Auto-generated method stub

super.onCreate(savedInstanceState);

setContentView(R.layout.speech_layout);

displayText = (TextView) findViewById(R.id.displayTextView);

Button speakButton = (Button) findViewById(R.id.speakButton);

speakButton.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

Intent in = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);

in.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, "en-US");

try {

startActivityForResult(in, 1);

} catch (Exception e) {

// TODO: handle exception

Toast.makeText(

getApplicationContext(),

"sorry, your device doesn't support speech to text feature",

Toast.LENGTH_LONG).show();

}

}

});

}

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

// TODO Auto-generated method stub

if (requestCode == 1) {

if (resultCode == RESULT_OK && data != null) {

ArrayList<String> text = data

.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);

displayText.setText(text.get(0));

}

}

super.onActivityResult(requestCode, resultCode, data);

}

}

The Final Result looks like this

  

Download the source code from below link

DOWNLOAD NOW